Message ID | 20200123195200.206355-1-jonathan@fintelia.io |
---|---|
State | New |
Headers | show |
Series | target/riscv: Disallow WFI instruction from U-mode | expand |
On 1/23/20 9:52 AM, Jonathan Behrens wrote:
> + if (!(env->priv >= PRV_S) ||
For integers, !(x >= y) is a poor way to write x < y.
r~
Haha, fair enough. I just copied that line from one of the other functions in that file, which all use the same style. The check is actually a bit worse than it looks because PRV_S is defined to be 1. Hence, the whole thing is equivalent to just writing `env->priv == PRV_U`. I can send out a new version with that changed. Jonathan On Thu, Jan 23, 2020 at 6:35 PM Richard Henderson < richard.henderson@linaro.org> wrote: > On 1/23/20 9:52 AM, Jonathan Behrens wrote: > > + if (!(env->priv >= PRV_S) || > > For integers, !(x >= y) is a poor way to write x < y. > > > r~ > >
diff --git a/target/riscv/op_helper.c b/target/riscv/op_helper.c index 331cc36232..2e5a980192 100644 --- a/target/riscv/op_helper.c +++ b/target/riscv/op_helper.c @@ -129,10 +129,10 @@ target_ulong helper_mret(CPURISCVState *env, target_ulong cpu_pc_deb) void helper_wfi(CPURISCVState *env) { CPUState *cs = env_cpu(env); - - if (env->priv == PRV_S && - env->priv_ver >= PRIV_VERSION_1_10_0 && - get_field(env->mstatus, MSTATUS_TW)) { + if (!(env->priv >= PRV_S) || + (env->priv == PRV_S && + env->priv_ver >= PRIV_VERSION_1_10_0 && + get_field(env->mstatus, MSTATUS_TW))) { riscv_raise_exception(env, RISCV_EXCP_ILLEGAL_INST, GETPC()); } else { cs->halted = 1;